The invention relates to an implant for implantation into an animal or a human body, comprising an axial inner portion for fixation inside the body and an axial outer portion extending outward from the body and serving for mounting of a device which can be detachably connected to the body via the ring.
There are numerous medical conditions in the gastrointestinal canal and in the urinary system which require a surgical intervention with temporary or permanent performance of a stoma. After such intervention, excrements or urine is traditionally collected in a stoma pouch, adhering to the skin and surrounding the stoma.
The demands for a tight adhesive surface are high. If liquid secretion penetrates the adhesive surface, this surface will loosen more or less, resulting in leakage from the pouch and release of an unpleasant smell.
Consequently, there is a demand for alternatives to traditional combinations of adhesive face plates and stoma pouches.
U.S. Pat. Nos. 4,265,244, 4,532,761 and 5,242,415 disclose partially biocompatible implants which form a leakproof fastening device for the stoma pouch after ostomy surgery. These implants all comprise a flange portion to form a fixed anchor for the implant in the body. The flange can be wholly or partly covered with a biocompatible mesh that enables and encourages tissue repair and ingrowth of the implant.
To enable implantation of a device with such a flange, it is necessary to make a relatively large incision in the abdominal wall for insertion of the implant. The construction of such implants being relatively large and rigid, the surgically treated patient frequently senses the presence of the implant which causes discomfort.
GB 2 019 219 discloses yet another implant with a rigid flange, extending horizontally from the conical body. The flange is perforated by a number of holes to facilitate growth therethrough of fresh tissue, thereby improving tissue bonding between implant and body. This construction is large in width as well and consequently requires a large surgical incision, and the presence of the flange causes considerable discomfort for the patient.
Many of the above disadvantages have been rectified by the implant known from international patent application PCT/EP98/04029, where the inventors of the present invention are co-inventors. There still remains a need for additional devices that can provide improved performance.
The present invention provides an implant of the kind mentioned above, which implant requires a smaller surgical incision than known so far with no direct mucocutaneous contact and which can be safely and securely affixed to an underlying skin layer or into a muscle without being fitted with a flange.
The invention also provides an implant which is not sensed by the patient after implantation, and which can be detachably attached to and/or disconnected from devices such as, e.g., caps or pouches, thereby giving the surgically treated patient unprecedented comfort.
The invention further provides an implant that causes an unprecedented minimum of allergic and inflammatory reactions.
In addition, the invention provides an implant that has an easily adjustable axial extension to fit heavy as well as thin patients.
The novel and unique features of the invention are based on the fact that in principle the implant has a generally tubular form, with an interior section comprising an anchoring ring and a continuous connecting section between this ring and an exterior section. The exterior section has at least one throughgoing transverse opening.
When the connecting section of the interior section is a rod extending between the anchoring ring and the exterior section, a single opening is produced between them. When the connecting section of the interior section is more than one rod extending between the anchoring ring and the exterior section, the connecting section is constructed as an open grid. Particularly appropriately, the rods may be evenly distributed along the anchoring ring and the exterior section.
When in this way at least one throughgoing transverse opening is produced between the interior section and the exterior section of the ring, new healed tissue and vascular systems can naturally form through such transverse opening(s) in such a way that in the course of very short time, a natural blood supplied biological fastening of the implant to the body will be established with, in the course of implantation, the implant being at least partly embedded into the body.
The total quantity of non-biological material embedded into the body and in direct contact with body tissue will be considerably smaller than that provided by other known devices so far. The risk and the probability of allergic and inflammatory reactions have therefore been reduced significantly in a simple way and are far smaller than when previously established devices are used.
A part of the axial extension of the at least one throughgoing transverse opening may in some cases advantageously be left outside the body, allowing ingrowth through the at least one transverse opening to occur partly on the outside and over cutis. In this way, only an insignificant part of the implant is implanted, while at the same time a strong fixation is secured.
At the end facing the connection section, the exterior section of the implant can advantageously be fitted with a ring-shaped section with a number of evenly distributed suturing perforations. By securing the implant solidly in a skin layer by suture through the suturing perforations in the first phase after surgery, the implant can be fixated at the required site in a simple manner. Thus, when the implant has been made resistant to compressive and tensile stress in this way, optimal conditions have been procured for the subsequent tissue healing phase, where fresh tissue grows through the transverse opening(s).
By, e.g., producing several rings of suturing perforations, a possibility of leaving a larger or smaller part of the implant outside the body is created. In this way, suturing can be performed either in cutis or in subcutis or in both skin layers, depending on how much of the exterior section of the implant is desired to remain outside the body.
In a second embodiment of the invention, the end opposite the exterior section of at least one of the rods of the connecting section tapers. When each rod tapers towards the free end, the implant can slidably be inserted readily through the skin around, e.g., a stoma using a very simple implantation method, and subsequently it can slidably be inserted further down towards an underlying muscle or fascia.
In an alternative implantation method, a number of insertion apertures corresponding to the number of rods can be made in the abdominal wall, serving to accommodate the rods.
Marking of insertion apertures can be made either by simple sketching and making them one at a time, or by simultaneous marking of all apertures by a purpose-designed cutting former plate for making an aperture for each rod at one time. In this way, the depths and widths of all apertures are ensured in a simple way for accurate accommodation of the rods to the necessary extent.
At least one throughgoing hole can be made at the free end of each rod, with the hole being arranged for accommodating at least part of the anchoring ring. When an anchoring ring of a material which is the same as or similar to, e.g., the implant is led through the holes of the rods, fastening between implant and body will become exceptionally strong. Consequently, the implant becomes immediately resistant to compressive and tensile stress, and the anchoring ring locks the implant in the tissue layer, where placement of the rods is chosen and through which the anchoring ring is forced.
When the ring is slidably inserted through the holes in the rod, the ring, the interior section and the rods together form transverse openings, corresponding to the previously mentioned transverse openings, in which subsequent appropriate attachment of a number of anchoring means is enabled. Similarly, a space between anchoring means and transverse openings can, as described above, be provided by means of antimicrobial impregnated threads.
This embodiment of the implant provides an extremely strong fastening in the tissue, and the implantation only requires a very small surgical intervention. If removal of the implant may be required at a later stage, this can be done in a simple way by removal of the ring fixating the implant first and subsequent removal of tissue formation at the suturing perforations, if any, whereupon the implant can be pulled out in a simple manner.